In order to protect the occupants of a vehicle in case of an accident, such as a frontal impact between two cars, vehicles are normally equipped with an interior safety system including safety belts, airbags and devices for protecting or restraining the movement of e.g. the knees or legs of occupants. With regard to the front-row passenger seat a glove box is normally placed in front of the knees of an occupant sitting in this seat. Knee safety devices are therefore commonly combined with the glove box.
Various knee safety devices have been disclosed in the past. US 2004/0124623 discloses a device comprising a glove box mounted via support members to a cross member located behind the dashboard. The glove box is provided with grooves arranged such that the glove box can collapse, or its side walls deform by bending, and thereby absorb impact energy if the knees of the occupant hit the glove box.
U.S. Pat. No. 4,427,215 discloses a device where a deformable restraining member is positioned in the lid of the glove box as to absorb the impact energy.
U.S. Pat. No. 5,071,162 discloses a device having a shock absorbing member in the form of a plate made of overlapping steel sheets arranged in the lid of the glove box. In the event of a knee impact on the glove box, the shock absorbing member absorbs impact energy by plastic deformation.
U.S. Pat. No. 5,190,314 discloses a glove box structure wherein two resiliently bending metal plates are mounted to a crossbar extending in the vehicle's rear direction with the glove box secured on the underside of the plates. In the event of an impact on the glove box the metal plates absorb energy by bending.
U.S. Pat. No. 5,431,442 discloses a structure where a weaker intermediate wall of the glove box is compressed, deformed and broken, thereby absorbing crash energy.
U.S. Pat. No. 6,299,208 discloses a system comprising knee guard brackets with U-shaped or C-shaped cross section mounted to a transverse support beam and extending towards the rear of the vehicle. The lid of the glove box is positioned outside the brackets such when the glove box lid is subject to an impact the brackets absorb energy by buckling deformation.
U.S. Pat. No. 6,948,738 discloses a device comprising cuff plates and a load distributor mounted to a supporting tube and positioned in front of the knees of an occupant sitting in the front seat. In the event of a frontal impact the knees of the occupant hit the load distributor and the impact energy is absorbed by rolling deformation of the cuff plates.
Conventional knee safety devices, such as the ones described above, normally work well when the knees of an occupant hit the structure in a way that has been considered in the design of the device. However, if a knee hits the structure in an unexpected way, the function of these devices is uncertain since they are sensitive to different positions or directions of impact.
Another disadvantage of conventional knee safety devices is that it is rather difficult to carry out readjustments of the device which normally is required to consider the large number of parameters affecting the function, such as friction between occupant and seat.
Many conventional devices also suffer from the disadvantage that energy absorbing members are placed at the side of the glove box, which makes it necessary to make the glove box narrower and thus less suitable for storage.